Beverages, particularly draught beer, are usually delivered to outlets like restaurants and bars in large metallic kegs. The kegs are closed by means of a closure that can be connected in a bar by means of a metallic dispense head. The dispense head connects the beer keg to a delivery line for delivery of the beer from the keg to the bar tap and to a gas line that feeds propellant gas into the keg for driving the beer out of the keg. Different breweries use different types of closures and therefore the bar has to have the right type of dispense head that fits the specific closure of the beer keg in question. In order to be able to switch between different types of kegs with associated different types of dispense heads, the bar or restaurant has to keep several dispense heads in stock. One of the many drawbacks of these metallic kegs and the associated metallic closures is that they are expensive to manufacture and therefore have to be used several times. Thus, there is a need of thorough cleaning of the keg and the dispense head and the connected delivery line and gas line. In the case of the keg, cleaning is done at the brewery, but the dispense head and the delivery and gas lines have to be cleaned in the restaurant or bar. This is a time consuming task which is most likely sometimes overlooked in restaurants and bars.
Recently plastic containers for draught beer have been developed, as well as plastic closures. These plastic closures are, however, very complex. There are examples with as many as 17 different parts. This makes manufacture complicated and expensive. With these closures it is necessary to fill the container through the closure and first the container and closure are rinsed with carbon dioxide through the closure in order to remove oxygen from the inside of the container and the closure. Oxygen might otherwise spoil the beverage.